To join a Group in Geochat you have two options:
Groups in Geochat are also divided into two different types:
In the public groups page you will see a list of groups. You can search in the list using the search box or just browse the list and select a group. There you will be able to:
You can be invited to join a group, you will be able to see the invitations in the Pending Invitations folder inside My groups
If you click on Pending Invitations you will see the list of invitations there you can either accept or reject the invitation by clicking in the correspondent link.
You can also leave the group by clicking on the leave group button at the end of each group page. You will be able to leave a group if you are not the only owner of it.